Extreme Weather and Coastal Challenges in Southern California

Days of intense weather are imminent, including extreme heat and high humidity, following a dramatic weekend of coastal flooding, rain, and hazardous surf brought by the remnants of Tropical Storm Marie. A significant increase in temperature is forecasted by Tuesday, with heat expected to rise “10 to 20 degrees above normal” across even coastal areas.

Rising Temperatures and Heat Stress

Downtown Los Angeles and Long Beach might experience temperatures as high as 96 to 98 degrees. Further inland and valley regions could see temperatures surpassing 105 degrees. Little relief is expected at night, with low temperatures likely remaining in the mid-70s across the Los Angeles Basin. Forecasters predict even warmer conditions on Wednesday.

The remaining moisture from Marie, combined with the heat, will increase heat discomfort and stress, said David Gomberg, lead meteorologist at the National Weather Service in Los Angeles-Oxnard. A heat advisory has been issued for Wednesday and Thursday, with preparations to upgrade warnings if conditions worsen.

If expected cloud cover does not develop, temperatures could rise significantly on Wednesday, according to Gomberg. He advises residents to stay hydrated, remain in air-conditioned environments, and check on vulnerable family members and neighbors.

Coastal Conditions and Safety Advisories

Advisories for high surf and coastal flooding are in effect until 11 p.m. Tuesday. Officials warn of dangerous ocean conditions due to Tropical Storm Marie. Rip currents and large surf pose risks to small boats, beachgoers, and swimmers.

Inexperienced individuals should avoid the surf zone now. Initially moderate waves can escalate to large, dangerous ones, Gomberg noted. He highlighted the presence of strong rip currents, described as potentially life-threatening.

In Malibu, waves at Zuma Beach reached 12 feet over the weekend. Emergency services responded to significant beach closures and coastal flooding, especially impacting areas like Long Beach and Malibu facing southward, affected by high swells and tides.

Coastal Damage and Power Issues

Video from Long Beach shows large waves crashing ashore and damaging the boardwalk. Pre-built sand berms were destroyed. Local residents face power outages, flooded garages, and sand-blocked drains. Power shortages are causing shocks, so we’re turning the power off. Tiles and furniture are getting displaced, said Long Beach resident Cole Hill.

Contributing Weather Factors

Southern California typically experiences tropical storms this time of year. However, extreme surf and tides due to the recent storm are striking. Colder water occupies less volume, while warmer water expands. The recent oceanic heat wave off California, coupled with the evolving El Niño, has increased tide levels beyond what is usual.

High tide levels, typically between 4 and 6.5 feet, reached 6.7 feet on Sunday. Forecasts predict levels up to 7 feet by Monday evening and 7.2 feet by Tuesday. Slight differences in water level significantly impact coastal flooding potential, explained Gomberg.

Impact of Rainfall and Water Quality Concerns

Unexpected rainfall over the weekend worsened drainage problems. Some areas of Los Angeles County accumulated over 1.25 inches of rain on Sunday. As a precautionary measure, public health officials advise avoiding ocean swimming through Wednesday due to potential bacterial contamination from rain.

The topography of Los Angeles County funnels rainwater mixed with various pollutants directly into the ocean. Unlike treated sewage, this runoff isn’t filtered before reaching the sea. Experts recommend waiting three to five days post-rainfall before entering the ocean, especially near river outflows.